He is accused of entering the storeand concealing the blind down one trouser leg and up the back of his jacket.
"Police have released a picture of a man who they wish to trace in connection with an alleged theft of a venetian blind," Northamptonshire Police said in a statement.
"He then left the store making no attempt to pay for the item. He was followed by staff up a nearby canal path, where he dropped the blind before making off.
"The blind was damaged as a result. Officers would like to speak with the man pictured."